The steel industry has warned Donald Trump’s threatened tariffs would be a “devastating blow”.
The US President said he plans to impose a 25% levy on “any steel coming into the United States”, adding that aluminium will also be subject to additional duties.
The steel industry body urged Sir Keir Starmer to take action to protect the sector.
UK Steel director general Gareth Stace said if Mr Trump went ahead with the levy it “would be a devastating blow to our industry” and “damage over £400 million worth of the steel sector’s contribution to the UK’s balance of trade”.
He added: “It is deeply disappointing if President Trump sees the need to target UK steel, given our relatively small production volumes compared to major steel nations.
“The UK produces world-leading steel, supplying the US with high-quality products for defence, aerospace, stainless, and other critical sectors, materials that simply cannot be replicated elsewhere.”
The UK exported 166,433 tonnes of steel to the US in 2023, the last full year for which figures are available.
Figures from trade body UK Steel showed that in 2024 some 162,716 tonnes were sent to the US, but that does not yet include data from December.
The US is the industry’s second-largest export market after the EU, although the Government said it only accounted for 5% of UK steel exports in 2023.
lasdair McDiarmid, assistant general secretary at trade union Community, said: “At a time of uncertainty for the sector, a punitive new tariff on UK steel exports would be hugely damaging and threaten jobs.
“For the US it would also be self-defeating, as the UK is a leading supplier of specialist steel products required by their defence and aerospace sectors.”
Unite union general secretary Sharon Graham said: “Donald Trumps’s steel tariff threat should be a wake-up call for this Government. I have long been calling for the steel industry to be classified as critical national infrastructure – just as it is in the US.
“UK steel production is a matter of national security. We now need to change the rules to ensure that the public sector buys UK produced steel, wherever it is available. This will create jobs and drive growth.”
Downing Street said the UK and US “work closely together on a range of economic issues, supporting jobs” on both sides of the Atlantic.
“I haven’t seen any detailed proposals following the reporting overnight, but we will obviously engage as appropriate,” the Prime Minister’s official spokesman said.
He added that he would not be drawn into saying whether the UK would retaliate in the event the US did impose tariffs, describing the question as hypothetical.
The UK steel industry was hit with tariffs in 2018 during Mr Trump’s first term in office, but those import taxes were eased in 2022.